Apparatus And Method For Maintaining Cooked Food In A Ready-To-Use Condition

ABSTRACT

A food warming apparatus includes a heating compartment that can hold one or more trays containing previously cooked food portions. A cover for a tray has a horizontal section and a vertical section extending downwardly from one side of the horizontal section. A rack in the heating compartment includes a channel and a stop that blocks the front end of the channel. The vertical section of the cover fits securely in the channel behind the stop such that the rack supports the cover substantially only through the vertical section. When a tray is inserted into the receiving space cooperatively defined by the cover and rack, the cover is lifted up so that the horizontal section rests on the tray and at least partially blocks the open top of the tray, thereby restricting evaporation of liquids from the previously cooked food portions contained in the tray.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to the field of food preparation. Moreparticularly, this invention relates to an apparatus and method formaintaining in a ready-to-use condition cooked food portions containedin a food tray, wherein a cover comprising a horizontal section and avertical section is used to cover the food trays.

2. Description of Related Art

In many establishments, such as fast food restaurants, certain fooditems are cooked well in advance of when they are ordered by or servedto the customer. Examples of such food items can include sandwichfillings, such as cooked eggs, hamburger patties, breaded foods, such aschicken nuggets, or baked goods, such as muffins. These previouslycooked food items are often maintained in a ready-to-use condition untilthey served to the customer. This typically involves maintaining thepreviously cooked food items at a serving temperature in the range offrom about 140° F. to about 200° F., depending on the food item.

Various food warming apparatus have been developed to maintainpreviously cooked food items at a desired serving temperature. Such foodwarming apparatus are sometimes referred to as staging cabinets, holdingcabinets, or warming cabinets. One of the challenges associated withfood warming apparatus is being able to preserve the flavor, appearance,and texture of the previously cooked food items while they are beingmaintained at the desired serving temperature. In particular, certaintypes of food items, such as cooked eggs and hamburger patties have atendency to dry out undesirably when they are kept warm for extendedperiods of time.

One commonly used way to protect previously cooked food items for whichdrying out is a concern, is to place the food items in a container, suchas a tray, and to provide a cover for the container. The cover restrictsevaporation of moisture from the previously cooked food items. With areduced amount of moisture vapor being able to escape from the coveredcontainer, the previously cooked food items contained therein do not dryout as rapidly.

Conventional covers are inconvenient to use in food fast restaurants andsimilar establishments. This is because when previously cooked foodportions are taken from the food warming apparatus, the cover typicallymust be removed from the tray to gain access to the food items containedtherein, and must be replaced to protect the remaining food portionscontained in the tray. The steps of removing and replacing a cover cantake an amount of time that is unacceptably large in fast foodrestaurants. The removed cover can also become misplaced or contaminatedand can get in the way of other activities in the kitchen area.

SUMMARY

In a first principal aspect, an exemplary embodiment provides a foodwarming apparatus for maintaining previously cooked food portionscontained in at least one tray in a ready-to-use condition. The at leastone tray has a lip defining a tray opening. The food warming apparatuscomprises a cabinet having at least one heating compartment therein. Arack is disposed in the at least one heating compartment. At least onecover has a horizontal section and a vertical section extendingdownwardly from one side of the horizontal section. The at least onecover is removably mounted on the rack such that the rack supports theat least one cover substantially only through the vertical section. Theat least one cover and at least one support member cooperatively defineat least one receiving space for receiving the at least one tray.

In a second principal aspect, an exemplary embodiment provides a methodfor covering a tray in a food warming apparatus. The food warmingapparatus includes a heating compartment. The tray has a lip defining atray opening. In accordance with the method, a rack that fits into theheating compartment is provided. A cover for the tray is provided. Thecover has a horizontal section and a vertical section extendingdownwardly from one side of the horizontal section. The cover is mountedon the support such that the rack supports the cover substantially onlythrough the vertical section. The tray is inserted into a receivingspace cooperatively defined by the cover and the rack until thehorizontal section of the cover rests on the lip of the tray and atleast partially blocks the tray opening.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an isometric view of a food warming apparatus, in accordancewith an exemplary embodiment.

FIG. 2 is an isometric view of a rack, in accordance with an exemplaryembodiment.

FIG. 3 is a front view of the rack of FIG. 2, in accordance with anexemplary embodiment.

FIG. 4 is a top view of the rack of FIG. 2, in accordance with anexemplary embodiment.

FIG. 5 is an isometric view of two covers and two trays, in combinationwith the rack of FIG. 2, in accordance with an exemplary embodiment.

FIG. 6 is a front view of the combination of FIG. 5, in accordance withan exemplary embodiment.

FIG. 7 is an isometric view of the combination of FIG. 5, with one ofthe trays removed, in accordance with an exemplary embodiment.

FIG. 8 is a front view of the combination of FIG. 5, with one of thetrays removed, in accordance with an exemplary embodiment.

FIG. 9 is a front view of a heating compartment in which two trays aresupported by a rack and the covers are supported by the rack and byadditional support members, in accordance with an exemplary embodiment.

DETAILED DESCRIPTION 1. OVERVIEW

A food warming apparatus is able to maintain previously cooked foodportions in a ready-to-use condition. The previously cooked foodportions may be placed in one or more open-top containers, which arereferred to herein as “trays.” The trays containing the previouslycooked food portions may be placed in one or more heating compartmentsto maintain the portions at a desired temperature. Covers may cover someor all of the trays in the heating compartments so as to restrictevaporation of moisture or other liquid from the previously cooked foodportions.

One or more support structures may be placed in the heating compartmentsto support covers independently of the trays. Thus, a tray may becovered by inserting it into a heating compartment, in which a coverthat is supported by a support structure is already in place. Inaddition, one or more stops may be used to retain the covers in theheating compartments. That way, when a tray is withdrawn from a heatingcompartment, the cover stays inside the compartment.

The support structure used to support the cover may include a rack. Therack may include a frame and a plurality of channel members that extendbetween the front of the frame and the back of the frame. Two adjacentchannel members may define a channel therebetween that can be used tosupport a cover within the heating compartment. In particular, the covermay have a horizontal section and a vertical section that extendsdownwardly from one side of the horizontal section. The vertical sectionmay be securely fitted into the channel so that the rack supports thecover substantially only through the vertical section of the cover. Forexample, the channel may be only slightly wider than the thickness ofthe vertical section. That way, the channel can substantially preventthe vertical section from moving in a side-to-side direction while stillallowing the vertical section to move in a vertical direction. Further,a bar that blocks the front end of the channel may function as a stopthat retains the cover in the heating compartment when the tray isremoved.

In this arrangement, the cover and the rack cooperatively define areceiving space for receiving a tray. Thus, a tray containing previouslycooked food portions may be placed in the heating compartment byinserting it into the receiving space. When the tray is fully inserted,the horizontal section of the cover at least partially blocks the opentop of the tray, so as to restrict evaporation of liquid from thepreviously cooked food portions contained in the tray.

In an exemplary embodiment, the insertion of the tray into the receivingspace moves the cover upwardly. In particular, before the tray isinserted into the receiving space, the vertical section may be disposedin the channel in a lower position in which the vertical section restson the frame. However, the height of the tray may exceed the height ofthe receiving space. As a result, when the tray is inserted into thereceiving space, the cover may move upwardly so that the verticalsection moves to an upper position above the frame and the horizontalsection rests on the tray. When the tray is subsequently removed, thevertical section returns to the lower position in the channel.

Although the rack can support a cover substantially only on one side,i.e., through the vertical section of the cover, it is to be understoodthat one or more additional support structures may be used to provideadditional support for the cover. For example, a rack may be used tosupport one side of the cover (e.g., through the vertical section) and asupport member separate from the rack may be used to support theopposite side of the cover (e.g., through the horizontal section).

Configuring the covers so that they stay in the heating compartment canprovide benefits for establishments such as fast food restaurants. Inparticular, a tray containing previously cooked food portions may beinserted into the heating compartment and covered in one step, and thetray may be withdrawn from the heating compartment and uncovered in onestep, thereby saving time. In addition, the inconvenience and thepossibilities of contamination associated with direct handling of coverscan be reduced.

2. EXEMPLARY FOOD WARMING APPARATUS

With reference to FIG. 1, an exemplary food warming apparatus 10includes a housing or cabinet 12 that has a top 14, a bottom 16, a front18, a back 20, and sides 22. The interior of cabinet 12 is divided intoheating compartments 24, 26, 28, and 30. Although FIG. 1 shows exemplaryfood warming apparatus 10 with four heating compartments, it is to beunderstood that a food warming apparatus could be provided with agreater or fewer number of heating compartments.

In the example shown in FIG. 1, front 18 is open to provide access tocompartments 24, 26, 28, and 30. However, it is to be understood thatback 20 could also be open to provide access to compartments 24, 26, 28,and 30, for example, in a pass-through configuration. Each ofcompartments 24, 26, 28, and 30 includes an upper compartment surfaceand a lower compartment surface. Thus, compartment 24 includes an uppercompartment surface 32 and a lower compartment surface 34, as shown inFIG. 1. Compartments 26, 28, and 30 may be similarly configured.

Each of compartments 24, 26, 28, and 30 is sized to accommodate one ormore trays, as exemplified in FIG. 1 by trays 40 and 42 in compartment24. Although FIG. 1 shows two trays in each compartment, it is to beunderstood that the compartments may be sized to accommodate a greateror fewer number of trays. In addition, although FIG. 1 shows eachcompartment filled with its maximum number of trays, it is to beunderstood that a compartment might hold less than the maximum number oftrays at any given time.

In each compartment, trays may be supported by a support structure suchas a rack. For example, FIG. 1 shows trays 40 and 42 in compartment 24supported by a rack 44. The rack may be mounted in the compartment invarious ways. For example, a rack could rest on lower compartmentsurface 34. Alternatively, a rack could be supported above lowercompartment surface 34. In the example illustrated in FIG. 1, the rackin each compartment is supported above the lower compartment surface bymounting brackets disposed on the side walls of the compartment. Thus,compartment 24 is shown with mounting brackets 45 supporting rack 44.

Covers may cover some or all of the trays in the compartments. Forexample, trays 40 and 42 in compartment 24 may be covered by covers 46and 48, respectively. The operational relationship between trays 40 and42, rack 44, and covers 44 and 46 is described in more detail below.

Each of compartments 24, 26, 28, and 30 may be heated by a respectiveheating system. In an exemplary embodiment, each heating system includesone or more resistive heaters for heating its respective compartmentfrom above and/or from below. For example, compartment 24 may be heatedthrough upper compartment surface 32 by heater plates 50 and 52, whichmay be positioned over trays 40 and 42, respectively. Compartment 24 mayalso be heated through lower compartment surface 34 by similar heaterplates. Compartments 26, 28, and 30 may be heated in a similar manner.

Food warming apparatus 10 may include various controls for enabling anoperator to control its operation and various indicators for displayinginformation to the operator. Some of the controls and indicators may bearranged in a control panel 54 disposed on front 18. Other controls andindicators may be arranged in interface bars 56, 58, 60, and 62,associated with compartments 24, 26, 28, and 30, respectively.

Control panel 54 may enable the operator to select setpoint temperaturesfor the compartments (or for specific trays in the compartments). Acontrol system in food warming apparatus 10 may control the heatingsystems for the compartments (e.g., thermostatically) so as to achieveand maintain the setpoint temperatures. In an exemplary embodiment, thecontrol system may measure the temperature at the heating system (e.g.,at heater plate 50 or 52), so that the setpoint temperature correspondsto the temperature at the heating system. The temperature of the foodinside of the covered tray in the compartment may be lower than thesetpoint temperature. For example, it may be desirable to maintainpreviously cooked food portions at a temperature that may range fromabout 140° F. to about 200° F. To achieve this food temperature, thesetpoint temperature may need to be as high as 400° F.

Interface bars 56, 58, 60, and 62 may each enable an operator to selecta hold time for the respective compartment (or for a specific tray inthe compartment) based, for example, on the particular food productcontained in the compartment (or contained in a specific tray in thecompartment). The operator may select the hold time by scrolling througha list of food products, each of which has been associated with a presethold time. A display on the interface bar may display descriptions ofthe food products as the operator scrolls through the list and may thendisplay a description of the selected food product.

When the selected food product is placed in the compartment, theoperator may interact with the compartment's interface bar to start atimer. When the hold time has been reached, the compartment's interfacebar may provide an indication to the operator. The operator may thenreplace the food product with fresh food product and interact with theinterface bar to re-set the timer.

3. EXEMPLARY RACK

FIGS. 2, 3, and 4 are isometric, front, and top views, respectively, ofrack 44. In this example, rack 44 includes a frame 100 and variousmembers extending upwardly from frame 100. Frame 100 may be mounted incompartment 24 as shown in FIG. 1, i.e., supported by mounting bracket45. Alternatively, frame 100 may rest on lower compartment surface 34.

The front of frame 100 may be defined by one or more laterally-extendingfront members 102, and the back of frame 100 may be defined by one ormore laterally-extending back members 104. Frame 100 may further includea plurality of cross-pieces 106 extending between front members 102 andback members 104. Alternatively, cross-pieces 106 could be omitted fromframe 100, in which case trays 40 and 42 may rest on lower compartmentsurface 34 after sliding over front members 102.

Rack 44 may also include channel members 108, 110, 112, and 114extending between front members 102 and back members 104. Channelmembers 108 and 110 define a first channel 116, and channel members 112and 114 define a second channel 118. As described in more detail below,first channel 116 receives a vertical section of cover 46, and secondchannel 118 receives a vertical section of cover 48.

As best shown in FIGS. 2 and 3, channel members 108, 110, 112, and 114may be configured as brackets that extend to a certain height aboveframe 100. In particular, channel members 108 and 114 may extend to agreater height above frame 100 than channel members 110 and 112.

Rack 44 may further include a stop 120 that blocks the front ends ofchannels 116 and 118. As best shown in FIG. 4, stop 120 may be providedas a bar that extends between channel members 108 and 114. A similarstop could also be provided to block the back ends of channels 116 and118.

Channel members 108 and 114 may also extend in front of stop 120 toprovide a handle 122. As shown in FIG. 1, handle 122 may extend out ofthe open front of compartment 24.

Rack 44 may also include side members 124 and 126 extending betweenfront members 102 and back members 104. Side members 124 and 126 maycooperate with channel members 108 and 114 to laterally position 40 and42 on rack 44. In particular, side member 124 and channel member 108 maydefine a space therebetween for receiving tray 40. Similarly, sidemember 126 and channel member 114 may define a space therebetween forreceiving tray 42.

4. EXEMPLARY COVERS

FIGS. 5 and 6 are isometric and front views, respectively, of acombination in which trays 40 and 42 are supported by rack 44 and arecovered by covers 46 and 48, respectively. Cover 46 has a horizontalsection 70 and a vertical section 72 attached to and extendingdownwardly from one side of horizontal section 70. Cover 48 similarlyhas a horizontal section 74 and a vertical section 76 attached to andextending downwardly from one side of horizontal section 74.

Vertical sections 72 and 76 may be fitted into separate channels, e.g.,with vertical section 72 in channel 116 and vertical section 76 inchannel 118. When vertical sections 72 and 76 are in channels 118 and118, respectively, they are also positioned behind stop 120.

In an exemplary embodiment, covers 46 and 48 are made out of a sheetmaterial. The sheet material could be a metal, such as stainless steel,aluminum, or titanium, with a thickness ranging from about 0.024 inchesto about 0.125 inches, depending on the type of metal. A metal covercould be anodized black or other color based, for example, on desiredthermal characteristics. It is to be understood that covers 46 and 48could also be made out of other materials, such as plastics (e.g., hightemperature Nylon, polysulfone, polyimide, polyethersulfone,polyetherimide, or polyphenylene sulfide), depending on the operatingtemperatures that the covers experience.

To construct a cover out of a sheet material, a generally rectangularpiece of the sheet material may be bent to an approximately 90 degreeangle so as to define a generally rectangular horizontal section and agenerally rectangular vertical section. The three free edges of thehorizontal section may also be bent to provide additional stiffness. Forexample, horizontal section 70 of cover 46 may include turned-up edges78 along three sides, and horizontal section 74 of cover 48 may includeturned-up edges 80 along three sides, as best shown in FIG. 5.Preferably, turned-up edges 78 and 80 do not contact upper compartmentsurface 32 when covers 46 and 48 are in compartment 24.

In the configuration shown in FIGS. 5 and 6, covers 46 and 48 aresupported by trays 40 and 42. In particular, tray 40 includes a lip 82on which horizontal section 70 of cover 46 rests, and tray 42 includes alip 84 on which horizontal section 74 of cover 48 rests. In addition,vertical sections 72 and 76 are in an upper position within channels 116and 118, such that the lower edges of vertical sections 72 and 76 do notreach down to the level of front member 102, as best shown in FIG. 6.

However, covers 46 and 48 change position when trays 40 and 42 areremoved. For example, FIGS. 7 and 8 illustrate how the position of cover48 changes when tray 42 is withdrawn from compartment 24. With tray 42no longer supporting cover 48, vertical section 76 is in a lowerposition within channel 118 such that the lower edge of vertical section76 rests on front member 102, as best shown in FIG. 8. In thisconfiguration, rack 44 supports cover 48 substantially only throughvertical section 76, due to vertical section 76 resting on front member102 and due to the narrowness of channel 118 substantially preventingside-to-side motion of vertical section 76. In general, the width ofchannel 118 will depend on the thickness of vertical section 76.Preferably, vertical section 76 fits sufficiently tightly in channel 118such that cover 48 does not tilt when supported in this way (i.e., suchthat vertical section 76 is substantially vertical and horizontalsection 74 is substantially horizontal). Preferably, a gap remainsbetween the top edge of channel member 114 and the underside ofhorizontal section 74, as best shown in FIG. 8. However, even if no suchgap is present so that horizontal section 74 contacts channel member114, rack 44 may still support cover 48 substantially only throughvertical section 76.

When tray 42 is withdrawn, cover 48 stays in compartment 24 because ofstop 120. In particular, when tray 42 is pulled forward, cover 48 may bepulled with it. However, the forward motion of cover 48 will be blockedwhen vertical section 76 in channel 118 reaches stop 120. In this way,stop 120 retains covers 46 and 48 in compartment 24.

In the configuration illustrated in FIGS. 7 and 8, cover 48 and rack 44cooperatively define a receiving space into which tray 42 can beinserted. The receiving space is defined above by horizontal section 74,defined below by front member 102 and defined along the sides by channelmember 114 and side member 126. However, the height of tray 42 isgreater than the height of the receiving space, i.e., the distancebetween front member 102 and horizontal section 74. As a result, whentray 42 is inserted into the receiving space, cover 74 is pushed upward,so that vertical section 76 lifts off of front member 102. When tray 42has been fully inserted, horizontal section 74 will again rest on lip84, as shown in FIGS. 5 and 6.

The double-headed arrow in FIG. 7 shows the directions in which tray 42may be inserted and withdrawn from under cover 48. Tray 42 may include ahandle 86 to facilitate its movement in the directions indicated by thedouble-headed arrow. Also as shown in FIG. 7, lip 84 may surround a topopening 88 that provides access to the interior of tray 42. The interiorof tray 42 defines a space that may be used to contain previously cookedfood portions. The height of this interior space may be defined by thedistance between a generally flat bottom wall 90 of tray 42 and theupper surface of lip 84. The sides of the interior space may be definedby four side walls 92 that extend between bottom wall 90 and lip 84.

5. EXEMPLARY METHOD OF USE

When tray 42 contains previously cooked food portions, tray 42 may beinserted under cover 48 in heating compartment 24 of food warmingapparatus 10 in order to maintain the previously cooked food portions ina ready-to-use condition. In particular, heating compartment 24 may beheated to maintain the previously cooked food portions at a desiredholding temperature, as described above. In addition, horizontal section74 of cover 48 may, at least partially, block top opening 88 so as torestrict evaporation of liquid from the previously cooked food portions.

Tray 42 may be withdrawn from compartment 24 in order to use one or moreof the previously cooked food portions, for example, to prepare a fooditem ordered by a customer. In particular, withdrawing tray 42 fromcompartment 24 allows an operator to access the previously cooked foodportions through the top opening of tray 42.

Covers 46 and 48 may be periodically removed from compartment 24, forexample, in order to clean them. To remove covers 46 and 48, trays 40and 42 may first be withdrawn from compartment 24. Then, rack 44 may bepulled out of compartment 24, e.g., using handle 122, with covers 46 and48 still mounted thereon. Once rack 44 has been withdrawn, covers 46 and48 may be lifted off.

Trays 40 and 42, rack 44, and covers 46 and 48 may be assembled incompartment 24 in the following way. First, covers 46 and 48 are mountedon rack 44. More particularly, cover 46 is mounted by fitting verticalsection 72 into channel 116 behind stop 120, and cover 48 is mounted byfitting vertical section 76 into channel 118 behind stop 120. With thisconfiguration, rack 44 supports cover 46 substantially only throughvertical section 72 and also supports cover 48 substantially onlythrough vertical section 76.

Once covers 46 and 48 have been mounted in this way, rack 44 may beinserted into compartment 24 through the front opening, e.g., usinghandle 122, so that frame 100 is supported by lower compartment surface34, by mounting bracket 45, or in some other way. Trays 40 and 42 maythen be inserted into compartment 24 by sliding them over front member102. After sliding over front member 102, trays 40 and 42 may drop to alower position (e.g., so that they are resting on cross-pieces 106 or onlower compartment surface 34). In this way, front member 102 may providea detent action that allows the user to feel when trays 40 and 42 arefully inserted in compartment 24. The insertion of trays 40 and 42 liftsup covers 46 and 48, as described above, to attain the configurationillustrated in FIGS. 5 and 6.

6. ADDITIONAL SUPPORT STRUCTURES

FIGS. 1-8 illustrate an embodiment in which the rack supports a coversubstantially only through the cover's vertical section when the coveris not covering a tray. However, other support structures may also beused to support covers. FIG. 9 illustrates an embodiment in whichsupport members 200 and 202 provide additional support for covers 46 and48, respectively.

In this embodiment, rack 44 is supported in compartment 24 by mountingbrackets 45 that are attached to the side walls of compartment 24. Rack44, in turn, supports trays 40 and 42, as well as their correspondingcovers 46 and 48. As before, rack 44 supports covers 46 and 48substantially only through their vertical sections 72 and 76, which aredisposed in channels 116 and 118, respectively. However, support members200 and 202 may also provide support for covers 46 and 48.

Support members 200 and 202 may be configured as 90-degree anglebrackets, each with a vertical side and a horizontal side. The verticalsides of support members 200 and 202 may be attached to the side wallsof compartment 24 above mounting brackets 45. The horizontal sides ofsupport members 200 and 202 may provide support surfaces for horizontalsections 70 and 74, respectively. For example, support members 200 and202 may be placed at a height within compartment 24 such that theysupport covers 46 and 48, respectively, when trays 40 and 42 are incompartment 24. Thus, horizontal sections 70 and 74 may rest on supportmembers 200 and 202 when trays 40 and 42 are present in compartment 24,as shown in FIG. 9. When trays 40 and 42 are withdrawn, covers 46 and 48may tilt so that vertical sections 72 and 76 drop down to their lowerpositions (e.g., resting on front member 102) but with horizontalsections 70 and 74 still resting on support members 200 and 202.

Alternatively, support members 200 and 202 may be placed at a lowerposition in compartment 24. For example, support members 200 and 202 maybe positioned such that horizontal sections 70 and 74 rest on supportmembers 200 and 202, respectively, before trays 40 and 42 are insertedinto compartment 24. Then, when trays 40 and 42 are inserted, horizontalsections 70 and 74 may be lifted off from support members 200 and 202and instead rest on trays 40 and 42.

It is to be understood that the configuration of support members 200 and202 shown in FIG. 9 and described above is exemplary only, as othertypes of support members may be used to provide support for covers inaddition to the rack.

7. CONCLUSION

While certain features and embodiments of the present invention havebeen described in detail herein, it is to be understood that theinvention encompasses all modifications and enhancements within thescope and spirit of the following claims.

1. A food warming apparatus for maintaining previously cooked food portions contained in at least one tray in a ready-to-use condition, said at least one tray having a lip defining a tray opening, said food warming apparatus comprising: a cabinet having at least one heating compartment therein; a rack disposed in said at least one heating compartment; and at least one cover having a horizontal section and a vertical section extending downwardly from one side of said horizontal section, said at least one cover being removably mounted on said rack such that said rack supports said at least one cover substantially only through said vertical section, said at least one cover and said rack cooperatively defining at least one receiving space for receiving said at least one tray.
 2. The food warming apparatus of claim 1, wherein said rack includes first and second channel members defining first and second sides of a channel, said vertical section being disposed in said channel.
 3. The food warming apparatus of claim 2, wherein said channel allows said vertical section to move in a vertical direction between at least a lower position and an upper position, and wherein said channel substantially prevents said vertical section from moving in a side-to-side direction.
 4. The food warming apparatus of claim 3, wherein said vertical section is disposed in said channel such that said vertical section moves from said lower position to said upper position when said at least one tray is inserted into said at least one receiving space and said vertical section moves from said upper position to said lower position when said at least tray is removed.
 5. The food warming apparatus of claim 4, wherein when said vertical section is in said upper position said horizontal section of said at least one cover at least partially blocks said tray opening so as to restrict evaporation of liquid from said previously cooked food portions contained in said at least one tray.
 6. The food warming apparatus of claim 4, wherein said rack includes at least one stop that retains said at least one cover in said at least one heating compartment when said at least one tray is removed.
 7. The food warming apparatus of claim 2, wherein said first channel member comprises a first bracket extending to a first height and said second channel member comprises a second bracket extending to a second height, said second height being greater than said first height.
 8. The food warming apparatus of claim 7, wherein said rack comprises a frame having a front and a back, said first and second brackets extending between said front and said back.
 9. The food warming apparatus of claim 1, wherein said at least one cover comprises a first cover and a second cover, said first cover having a first horizontal section and a first vertical section extending downwardly from one side of said first horizontal section, said second cover having a second horizontal section and a second vertical section extending downwardly from one side of said second horizontal section, and wherein said rack supports said first cover substantially only through said first vertical section and supports said second cover substantially only through said second vertical section.
 10. The food warming apparatus of claim 9, wherein said rack has a first channel defined by first-channel side members and a second channel defined by second-channel side members, and wherein said first vertical section is disposed in said first channel and said second vertical section is disposed in said second channel.
 11. The food warming apparatus of claim 1, wherein said at least one cover is metal.
 12. The food warming apparatus of claim 1, further comprising at least one heater plate for heating said at least one heating compartment.
 13. The food warming apparatus of claim 1, further comprising: at least one support member supporting said horizontal section, said support member being separate from said rack.
 14. A method for covering a tray in a food warming apparatus, said food warming apparatus including a heating compartment, said tray having a lip defining a tray opening, said method comprising: providing a rack that fits into said heating compartment; providing a cover for said tray, said cover having a horizontal section and a vertical section extending downwardly from one side of said horizontal section; mounting said cover on said rack such that said rack supports said cover substantially only through said vertical section; inserting said rack with said cover mounted thereon into said heating compartment; and inserting said tray into a receiving space cooperatively defined by said cover and said rack until said horizontal section of said cover rests on said lip of said tray and at least partially blocks said tray opening.
 15. The method of claim 14, wherein said rack defines a channel for receiving said vertical section of said cover, and wherein mounting said cover on said rack comprises: fitting said vertical section into said channel.
 16. The method of claim 15, wherein said rack includes a stop that blocks at least one end of said channel, and wherein fitting said vertical section into said channel comprises: positioning said vertical section behind said stop.
 17. The method of claim 16, further comprising withdrawing said tray from said heating compartment such that said stop prevents said cover from being withdrawn from said heating compartment as said tray is being withdrawn.
 18. The method of claim 17, wherein withdrawing said tray from said heating compartment comprises: said vertical section moving vertically in said channel from an upper position to a lower position.
 19. The method of claim 18, wherein inserting said tray into a receiving space cooperatively defined by said cover and said rack comprises: said vertical section moving vertically in said channel from said lower position to said upper position.
 20. The method of claim 14, further comprising: supporting said horizontal section by a support member separate from said rack. 